Edward ba



(No Model.)

E.l BAUSGH.

BINOGULAR MIGRsooPE.

No. 293,217. Patented Feb. l2, 1884.

@GQ/wmgvl, fig/6% ATTORNEY UNITED STATES EDYVl-Xlll) BVSH, OF ROCHESTER, Nlld' YORK,

EINOGULAR MICROSCOPE.

PATENT OEEICE,

SECIFICATION forming 'part of Letters Patent No. 293,217, dated February 1.?, 1&84,

Application Filed Dccemberr, lsi. (Xo model ,To all whom if, may concer/t:

Be it known that I, linuzrnn lxuscn, a citizen of the United States, resi dingin Rochester, .in t-he county of Monroe and State of New York, have invented a new and useful linprovementin Binocular Microscopes; and l do hereby declare that the following is a i'ull, clear, and exact description thereof, reference being had to the accompanying drawings, forming a part ot' this specilieation.

My invention relates to the class of microscopes in which part of the rays ot' light emanating from the object and passing through the objective are divided by a d'oubly-retleeting prism, known as the \Venham prism,77

' so that one-halt' lot' the rays pass to an auxil- 'lary eye-piece mounted in a branch tube applied to the side ol" the main tube. y,

In microscopes ot' this class the prism has heretofore been mounted in a box arranged to slide laterally in the lower part ot the mi croseope-body7 so that it could be moved into and out oi' its place by sliding the box, and any imperfection in the bearings of the box, which are necessarilyT narrow, allowed the box to move laterally, thereby impairing the eti 'lcetiveness ot' the instrument. Another serious objectionto the commonmethod ot`1nount ing the prism is, that the size ot tubes in niicroscopes being limited, and the box being contained entirely in the tube or nosepiece, the movement of the box and size ot' theprisni are correspondingly limited. This being the case, a large proportion ol' the rays which are i transmitted by modern objectives are prevented from passing to the eye-piece, so that it has frequently been i'ound necessary to remove the .nose-piece containing the ordinary prism-box and replace it by another nose-piece which had no obstruction when the 'l'ullelTectiveness of the objective Yas desired.

lu'y invention is designed to obviate these difficulties by providing a prisnrholdcr with a .long cylindrical. bearing, which is readily made and practically indestructible by wear, and which admits of either binocularormonocular arrangement of the microscope with the full etect of either method of vision.

It consists of a prism-carrying arm iixed to the end ot aspindle extending through asleeve passing through the side ot' the microscope body, the spindle beingprovided with amilled head,by which it is turned,and with a stop-pin, for limiting its motion.

In the drawings, Figure l. is a vertical section on line in Fig. L ol' a portion ot" amicroscope-body, showing my improvement ap* plied. Fig. 2 is a plan view, partly in section.

Lilie letters oi' reference indicate the same parts in the two figures.

rlhe bodyof the microscopeis provided with a nose-piece, A, threaded in the usual way at its lower end to receive an objective, and having sufficient depth to contain the prisnrliolder B. The prism-holder B consists ol" a metallic plate, c, bent twice at right angles, and receiving between its parallel sides b c the prism The side c ofthe holder B is prolonged, form` ing an arm, c,whichis secured in any suitable manner to the end ot' a spindle, l). In the present case it is fitted to a shoulder on the spindle and fastened by means of a small nut, d, iitted to the threaded end ot' the spindle. The spindle l) is fitted to a sleeve, E, passing through the side ot the nose-piece A, s'o that it may turn therein without lateral or longitudinal motion. To insure the perfect bearing of the spindle l) in the sleeve E the sleeve has a longitudinal slit, c, which permits it to adapt itself tothe spindle by springing and to create the small amount ot' friction necessary to retain the prism-holder in any position. The outer end ot' the spindle Dis provided with a milled head, F, by which the prism may be moved into or ont ofthe iield, and apin, projecting from the spindle through a slot, y, in the sleeve E, limits themotionoi' the prismholder in either direction. The prism -holder B is arranged relative to the main and auxiliary tubes of the microscope, so that it will swing in a plane lying in the axes ot' the two tubes, and when itis swung down into the p osition shown in full lines in the drawings the prism intercepts one-halt' et the rays passing through the objective a-nd diverts them to the auxiliary tube. NVhen the mi oroscopo is used for monocular vision, the prism is turned out of the iield, as indicated by dotted lines in Fig. l.

Havingthus described myinvcntion, what l claim as new, and desire to secure by Letters Patent, is-

1. In 2b binocular microscope, a swinging 3. The combination, in a binocular lnicro- 1o prisnrholder adapted to support the prism scope, of the prism C, prism-holder B, spindle within the body of Jshe microscope eitherin or D, provided with the stop-pin f, and t-he slotout of the iield of vision7 as herein specified. ted sleeve E, .as herein specified.

5 2. The combination with the doubly-recctl ,l l T ing prism )fabinooulai1 microscopepfa prisrn- ED ARD BAL SCH' supporting'arm and spindle attached thereto, XVit'ncsses: and extending outward through the niicro- CARL F. LOMB, scope-body7 as described. HENRYBAUSCI'I. 

